SLEEP EASE Think celebrities wake up every morning just like the rest of us? Think again! On the eve of his recent marriage, Batman & Robin star Chris O'Donnell wanted to make sure his Chicago house was outfitted with the best bed money can buy. Remembering how well he always sleeps at the Four Seasons Hotel in Los Angeles, he asked the concierge there how he could get the same bed. ''Just ask,'' he was told. Faster than you can say Batcave, the hotel arranged for a luxe comfy-mattressed king-sizer to be sent to him in the Midwest. ''Of course, the thing didn't fit in the front door, so we had to get a crane to bring it in through the bedroom window,'' says O'Donnell. The really hard part, though, is figuring out how to get those little chocolates on the pillow every night.